Artificial limb



ARTIFICIAL LIMB VI d? all? I,

Aprile 1948- H. M. wrrMYER Erm. l 2,439,195

\ RTIFICIAL LIMB Filed May 25. 1945` 2 Sheets-Sheet 2 y if Z f// .l l if ma@ @fwd/Mum posed a closely fitting bolt 2I the head 22 of which is within the recess I8 and the shankof which projects downwardly beyond the lower end of the socket member I2 and has, at its terminal end, a reduced threaded portion 23 upon which a nut 24 is'threaded. By reason of the close fit of the shank 2| of the bolt in the cylindrical aperture 20 of the socket member I2 the bolt is constrained to move with the socket member at all times and may be considered to be a downwardly extending axially disposed portion of the socket.

The ben member ef the connecting device is indicated generally at 30 and isseen to comprise an upper substantially spherical portion 3|, the

surface of which snugly engages at all times the spherical surface I9 of the socket memberl 2; and

a downward extension 32 in the nature of a hol- A side and the nut 24 on the other.

Thev axial aperture formed in the ball 30 through which the bolt 2| extends iscircular in all transverse sections vand is narrowest midway between its ends,A as clearly shown in Figures 1 and 2. Thusfrromits midpoint it ilares both upwardly and downwardly,` the purpose being to provide the bolt 2| 'with space throughV which the bolt may oscillate or rock about its centerof oscillation or. rocking movement, Le., the center of the ball member,-when .the device is in operation. When the socket I2 moves relatively to the ball 30 the boltwill move-angularly about the point C', which is the center 4of the spherical surfaces of the balland it is clear that the extent of rockiner movement or oscillation of the bolt about the point C will. be limited by the contact of the bolt with vthe walls of the, aperturev in the ball within which-it is located. In Figure 2 of the drawings the bolt is shown to have been tilted or rocked to the-limit of-its tiltingor rocking movement in one direction.. The angle through which the bolt may rock. from a vcentral .position may, of course,

be modified by increasing or decreasing the degreeof taper or flare 'of the upper and lower sectio-ns of the bolt-receiving recess in the ball.

The ball issecurely` attached to the artificial foot |I,7the lower endof the tubular portion 32 of the ball being exteriorly'threaded so as to receive a securing nuty 35, the upper surface of this nut being .parallel to the undersurface of the spherical portion 3| of the ball sothat these two surfaces a-re adapted to clampingly engage an intermediate annular lportion Ia of the artificial foot I I.. Suitable locking means, such as screw 35a. may be provided to prevent accidental loosening of nut 35, this screw being received in a threaded aperture in the nut and its pointed end being pressed into the annular portion Ia of. the foot. In assembling the device with the members l0 and the ball will be secured firmly to the foot member byY means of the nut 35 and the socket, with the bolt2l disposed within the opening 20, totheleg member I0 by means of the securing bolts `IVa'nd I5. The ball and socket members may then be placed in cooperative relationship and the boli; 2| positioned as shown, the ball-engaging nut 24 then being applied in such manner that part 34 closely engages the spherical lower end surface of the tubularpart 32 .of the ball. The parts are then in operative relationship and the lock nut may then be applied to insure that this relationship is maintained. The mouth ofthe aperture inthe Vfoot isthensealed to prevent the entry of dirt, awooden'or composition disc 46 being inserted and secured in posi- 'tion by means of a screw 41.

. VIn order to prevent the foot member from rotating about the longitudinal axis of the leg y member I0, i; e., from rotating about the axis of the Vbolt 2|, litis provided with inserts or plugs 4|1 the upper ends of which project respectively into recesses 4| formed in the lower surfaces of theleg portion I 0. The lower end surfaces of the leg portion I D are spaced from the substan- Y tiallyparallel mutuallyfacing surfaces of the foot portion Iljand there is placed intermediate these mutually facing surfaces a resilientgaske'tlikemem'ber43 which'is preferably of rubber. The resilient member 43 functions to maintain the ball and socket in coaxial relationship in the absence of, any forcetending'to move thesefparts angularly with ,relationY to each other, as when the user is walking, whilev atthe 'same time not interfering with, although cushioning, the 'angular relative movement ofthe connected leg members. Preferably the plugs 40'are formed as integral portions Vof, thefannular rubberjmember 43. Additional plugs40a are located upon vopposite sides, respectively, of the joint device, being located in alignedv recesses, respectively, erably integral with member43. j s y It willbe seenfrom Figure 2 that if the foot moves angularly with respect to the legmember that portion 0f the rubbercushionwhich lies to one side of the connecting'devicewill be compressed and that portion of the cushion which lies to the 'other sideA of the connecting device willbe allowed to expand. Thev arrangement is such, therefore; that the wearer isnot subjected to mechanical shock as the foot vrreaches the limit Y of its movement with respectto the legand the action is verymuch the saine., as ythat of theV normal ankle. The socket maywithadvantage be' fabricated of asbestos fiber treated` with phenolic resins,` or'of textile bers similarlytreated. It may be .formedof such materials by securing together sheets or laminations thereof, the assembled sheets thenV being machined if necessary. Y The 'socket may have a lubricant vsuch as graphite incorporated therein so as to maintain the interengaging `surfaces of the ball and socket satisfactorily' lubricated forthe vvlife of the connecting.

device. 'v Naturally, however, the Isocket may be fabricated of othensuitable materials, such as resin-treated pulps, or steel, bronze, brass, cast iron, aluminum or aluminum. alloys'.` v.The connection may be made of various sizes p to be incorporatedin limbs Vfor the useA of adults or children... a

,In Figures 6, 7 and 8there is vshown aA generally similarformvof artificial limbmember connecting device. Here the socket member B0 is connected. to the limbniember 5| byfbolts 32 identical with those shownin Figures 1 and `5,

and pref-* between the 1imb .members lto prevent penetration of dust and dirt to theconnecting balljoint. This sleevefmay be attachedtothe leg` member or to theilfoot member as` desired. AL similar sleeve 69 is employedin association with the limb members of the -formf of theinventi'on illustrated in Figures 1, 2 and 3.

If desired` the rubber gasket,` with itsV associated plugs or enlargements, may be of such thickness that it is under some compression at all times, both when the limb members are in normal relative position or in the relative positions in which they are shown in Figures 4 and '7. In such constructions spongy rubber may be utilized to insure that the relative angular movements of the limb members may not be restricted. The limb members may be constructed of any suitable material, the foot member being preferably fabricated of wood.

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is:

1. In an artificial limb, the combination with two parts to be connected together for limited angular movement of a ball mounted on one of` said members and a ball-engaging device mounted upon and movable with the other member,

whichzsthejf aperture in` the-ball varies; in crossl said ball-engaging device including elements l adapted to engage diametrically opposed spherical surfaces of the ball, and means connecting said elements and maintaining them in close sliding engagement with such surfaces of the ball.

2. In an artificial limb, the combination with two parts to be connected together for limited angular movement of a ball mounted on one oi said members and a ball-engaging device mounted upon and movable with the other member, said ball-engaging device including elements adapted to engage diametrically opposed spherical surfaces of the ball, and means connecting said elements and maintaining them in close sliding engagement with such surfaces of the ball, said means and ball having mutually engageable portions comprising stops for limiting the relative angular movements of the ball and ball-engaging device.

3. In an artificial limb, the combination with two parts to be connected together for limited angular movement of a ball mounted on one of said members and a ball-engaging device mounted upon and movable with the other member, said ball having an aperture extending therethrough and said ball-engaging device including elements adapted to engage diametrically opposed spherical surfaces of the ball and means extending through the aperture in the ball for 'connecting said elements and maintaining them in close sliding engagement with such surfaces of the ball.

4.' In an artificial limb, the combination with two parts to be connected together for limited angular movement of a ball mounted on one of said members and a ball-engaging device mounted upon and movable with the other member, said ball having an aperture extending therethrough and said ball-engaging device including elements adapted to engage diametrically opposed spherical surfaces of the ball and a bolt extending through the aperture in the ball for connecting said elements and maintaining them in close sliding engagement with such surfaces of the ball, contact between the bolt and ball limiting relative angular movements of said members.

5. The combination set forth in claim 4 in section from end to endflaringeoutwardly toward botli;dsifrmnits-midpoint, angular movement,oli/"thefblttrelativelgtoithe ball being limited by contact of thebolt and wall of the aperture. I

6i The.'combinationsetlforth inclaim 4 in which the bolt is provided with a nut for rela-` tively adjusting the ball-engaging elements.

7. The combination set forth in claim 1 in which one of said elements is formed as a substantially cylindrical block having at one end a spherical surface for engaging the ball and at the other end transversely extending apertures for the reception of securing bolts, and securing bolts extending through said Vapertures and through the part with which said blo'ck is asso ciated.

8. For use in connecting parts of articial limbs, a ball member having a substantially hemispherical portion and an integral hollow radially extending tubular portion with a spherical end surface, the hemispherical portion having an aperture therein which is aligned with the aperture of the tubular portion, a nut encircling and having threaded engagement with the tubular portion of the ball whereby the ball may be clamped to an annular limb part intermediate the nut and hemispherical portion of the ball, and means to be mounted upon a second limb part, said means being provided with elements for engaging said aforementioned spherical surfaces of the ball.

9. For use in connecting artificial limb parts, a ball comprising coaxial hemispherical and radially extending portions, the outer end surface of the radially extending portion being curved spherically about the axis of curvature of the hemispherical portion, a nut encircling and threaded upon said radially extending portion whereby a limb part may be clamped between the hemispherical portion of the ball and said nut, and means to be mounted upon a second limb part, said means being provided with elements for engaging said aforementioned spherical surfaces of the ball.

10. An articial limb comprising two parts and a device for connecting the same for universal movement about a central point, resilient means interposed between said parts and normally maintaining them in a predetermined angular relationship, and second means offset laterally from said device for limiting relative rotation of said parts about an axis extending longitudinally of one of them.

ll. An artificial limb comprising two parts and a device for connecting the same for universal movement about a central point, resilient means interposed between said parts and normally maintaining them in a predetermined angular relationship, and second 'means offset laterally from said device for limiting relative rotation of said parts about an axis extending longitudinally of one of them, said second means including a resilientmember intermediate said parts and adapted to assist in maintaining them in predetermined angular relationship as well as to limit their relative rotation about an axis extending longitudinally of one of them.

l2. An artiiicial limb comprising two parts and a device for connecting said parts for universal movement about a central point, the adjacent ends of said parts having registering recesses, and a resilient member extending into said recesses, said member opposing relative rotation REFERENCES CITED The following references are of record in the fue of this patent:

UNITED STATES PATENTS" Number Number Name Date Swank Aug. 5, 1890 Van Cise July 7, 1942 FOREIGN PATENTS Country Date France Feb. 27, 1928 

